4183 Commits

Author SHA1 Message Date
Guoqing Jiang
15858fa5b0 md-cluster: Defer MD reloading to mddev->thread
Reloading of superblock must be performed under reconfig_mutex. However,
this cannot be done with md_reload_sb because it would deadlock with
the message DLM lock. So, we defer it in md_check_recovery() which is
executed by mddev->thread.

This introduces a new flag, MD_RELOAD_SB, which if set, will reload the
superblock. And good_device_nr is also added to 'struct mddev' which is
used to get the num of the good device within cluster raid.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
2016-01-06 11:39:10 +11:00
Guoqing Jiang
f6a2dc64ee md-cluster: append some actions when change bitmap from clustered to none
For clustered raid, we need to do extra actions when change
bitmap to none.

1. check if all the bitmap lock could be get or not, if yes then
   we can continue the change since cluster raid is only active
   in current node. Otherwise return fail and unlock the related
   bitmap locks
2. set nodes to 0 and then leave cluster environment.
3. release other nodes's bitmap lock.

Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
2016-01-06 11:38:57 +11:00
Goldwyn Rodrigues
09afd2a8d6 md-cluster: Allow spare devices to be marked as faulty
If a spare device was marked faulty, it would not be reflected
in receiving nodes because it would mark it as activated and continue.
Continue the operation, so it may be set as faulty.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
2016-01-06 11:38:51 +11:00
Goldwyn Rodrigues
54a88392cd md-cluster: Fix the remove sequence with the new MD reload code
The remove disk message does not need metadata_update_start(), but
can be an independent message.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
2016-01-06 11:38:42 +11:00
Guoqing Jiang
659b254fa7 md-cluster: remove a disk asynchronously from cluster environment
For cluster raid, if one disk couldn't be reach in one node, then
other nodes would receive the REMOVE message for the disk.

In receiving node, we can't call md_kick_rdev_from_array to remove
the disk from array synchronously since the disk might still be busy
in this node. So let's set a ClusterRemove flag on the disk, then
let the thread to do the removal job eventually.

Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
2016-01-06 11:38:36 +11:00
Goldwyn Rodrigues
ac277c6a8a md-cluster: Avoid the resync ping-pong
If a RESYNCING message with (0,0) has been sent before, do not send it
again. This avoids a resync ping pong between the nodes. We read
the bitmap lockresource's LVB to figure out the previous value
of the RESYNCING message.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
2016-01-06 11:38:27 +11:00
Roman Gushchin
b46020aa3a md/raid5: remove redundant check in stripe_add_to_batch_list()
The stripe_add_to_batch_list() function is called only if
stripe_can_batch() returned true, so there is no need for double check.

Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
Cc: Neil Brown <neilb@suse.com>
Cc: linux-raid@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.com>
2016-01-06 11:38:22 +11:00
Al Viro
93bbf5831d md: more open-coded offset_in_page()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-04 10:29:12 -05:00
Al Viro
756d097b95 dm-bufio: virt_to_phys() doesn't change remainder modulo PAGE_SIZE
... so virt_to_phys(p) & (PAGE_SIZE - 1) is a very odd way to
spell offset_in_page(p).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-04 10:29:07 -05:00
Kent Overstreet
627ccd20b4 bcache: Change refill_dirty() to always scan entire disk if necessary
Previously, it would only scan the entire disk if it was starting from
the very start of the disk - i.e. if the previous scan got to the end.

This was broken by refill_full_stripes(), which updates last_scanned so
that refill_dirty was never triggering the searched_from_start path.

But if we change refill_dirty() to always scan the entire disk if
necessary, regardless of what last_scanned was, the code gets cleaner
and we fix that bug too.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-30 20:23:16 -07:00
Stefan Bader
8d16ce540c bcache: prevent crash on changing writeback_running
Added a safeguard in the shutdown case. At least while not being
attached it is also possible to trigger a kernel bug by writing into
writeback_running. This change  adds the same check before trying to
wake up the thread for that case.

Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-30 20:23:14 -07:00
Gabriel de Perthuis
d7076f2162 bcache: allows use of register in udev to avoid "device_busy" error.
Allows to use register, not register_quiet in udev to avoid "device_busy" error.
The initial patch proposed at https://lkml.org/lkml/2013/8/26/549 by Gabriel de Perthuis
<g2p.code@gmail.com> does not unlock the mutex and hangs the kernel.

See http://thread.gmane.org/gmane.linux.kernel.bcache.devel/2594 for the discussion.

Cc: Denis Bychkov <manover@gmail.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: Gabriel de Perthuis <g2p.code@gmail.com>
Cc: stable@vger.kernel.org

Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-30 20:23:13 -07:00
Zheng Liu
2ecf0cdb2b bcache: unregister reboot notifier if bcache fails to unregister device
In bcache_init() function it forgot to unregister reboot notifier if
bcache fails to unregister a block device.  This commit fixes this.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Tested-by: Joshua Schmid <jschmid@suse.com>
Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-30 20:23:11 -07:00
Al Viro
4d4d8573a8 bcache: fix a leak in bch_cached_dev_run()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Joshua Schmid <jschmid@suse.com>
Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-30 20:23:10 -07:00
Zheng Liu
fecaee6f20 bcache: clear BCACHE_DEV_UNLINK_DONE flag when attaching a backing device
This bug can be reproduced by the following script:

  #!/bin/bash

  bcache_sysfs="/sys/fs/bcache"

  function clear_cache()
  {
  	if [ ! -e $bcache_sysfs ]; then
  		echo "no bcache sysfs"
  		exit
  	fi

  	cset_uuid=$(ls -l $bcache_sysfs|head -n 2|tail -n 1|awk '{print $9}')
  	sudo sh -c "echo $cset_uuid > /sys/block/sdb/sdb1/bcache/detach"
  	sleep 5
  	sudo sh -c "echo $cset_uuid > /sys/block/sdb/sdb1/bcache/attach"
  }

  for ((i=0;i<10;i++)); do
  	clear_cache
  done

The warning messages look like below:
[  275.948611] ------------[ cut here ]------------
[  275.963840] WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xb8/0xd0() (Tainted: P        W
---------------   )
[  275.979253] Hardware name: Tecal RH2285
[  275.994106] sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:09.0/0000:08:00.0/host4/target4:2:1/4:2:1:0/block/sdb/sdb1/bcache/cache'
[  276.024105] Modules linked in: bcache tcp_diag inet_diag ipmi_devintf ipmi_si ipmi_msghandler
bonding 8021q garp stp llc ipv6 ext3 jbd loop sg iomemory_vsl(P) bnx2 microcode serio_raw i2c_i801
i2c_core iTCO_wdt iTCO_vendor_support i7core_edac edac_core shpchp ext4 jbd2 mbcache megaraid_sas
pata_acpi ata_generic ata_piix dm_mod [last unloaded: scsi_wait_scan]
[  276.072643] Pid: 2765, comm: sh Tainted: P        W  ---------------    2.6.32 #1
[  276.089315] Call Trace:
[  276.105801]  [<ffffffff81070fe7>] ? warn_slowpath_common+0x87/0xc0
[  276.122650]  [<ffffffff810710d6>] ? warn_slowpath_fmt+0x46/0x50
[  276.139361]  [<ffffffff81205c08>] ? sysfs_add_one+0xb8/0xd0
[  276.156012]  [<ffffffff8120609b>] ? sysfs_do_create_link+0x12b/0x170
[  276.172682]  [<ffffffff81206113>] ? sysfs_create_link+0x13/0x20
[  276.189282]  [<ffffffffa03bda21>] ? bcache_device_link+0xc1/0x110 [bcache]
[  276.205993]  [<ffffffffa03bfa08>] ? bch_cached_dev_attach+0x478/0x4f0 [bcache]
[  276.222794]  [<ffffffffa03c4a17>] ? bch_cached_dev_store+0x627/0x780 [bcache]
[  276.239680]  [<ffffffff8116783a>] ? alloc_pages_current+0xaa/0x110
[  276.256594]  [<ffffffff81203b15>] ? sysfs_write_file+0xe5/0x170
[  276.273364]  [<ffffffff811887b8>] ? vfs_write+0xb8/0x1a0
[  276.290133]  [<ffffffff811890b1>] ? sys_write+0x51/0x90
[  276.306368]  [<ffffffff8100c072>] ? system_call_fastpath+0x16/0x1b
[  276.322301] ---[ end trace 9f5d4fcdd0c3edfb ]---
[  276.338241] ------------[ cut here ]------------
[  276.354109] WARNING: at /home/wenqing.lz/bcache/bcache/super.c:720
bcache_device_link+0xdf/0x110 [bcache]() (Tainted: P        W  ---------------   )
[  276.386017] Hardware name: Tecal RH2285
[  276.401430] Couldn't create device <-> cache set symlinks
[  276.401759] Modules linked in: bcache tcp_diag inet_diag ipmi_devintf ipmi_si ipmi_msghandler
bonding 8021q garp stp llc ipv6 ext3 jbd loop sg iomemory_vsl(P) bnx2 microcode serio_raw i2c_i801
i2c_core iTCO_wdt iTCO_vendor_support i7core_edac edac_core shpchp ext4 jbd2 mbcache megaraid_sas
pata_acpi ata_generic ata_piix dm_mod [last unloaded: scsi_wait_scan]
[  276.465477] Pid: 2765, comm: sh Tainted: P        W  ---------------    2.6.32 #1
[  276.482169] Call Trace:
[  276.498610]  [<ffffffff81070fe7>] ? warn_slowpath_common+0x87/0xc0
[  276.515405]  [<ffffffff810710d6>] ? warn_slowpath_fmt+0x46/0x50
[  276.532059]  [<ffffffffa03bda3f>] ? bcache_device_link+0xdf/0x110 [bcache]
[  276.548808]  [<ffffffffa03bfa08>] ? bch_cached_dev_attach+0x478/0x4f0 [bcache]
[  276.565569]  [<ffffffffa03c4a17>] ? bch_cached_dev_store+0x627/0x780 [bcache]
[  276.582418]  [<ffffffff8116783a>] ? alloc_pages_current+0xaa/0x110
[  276.599341]  [<ffffffff81203b15>] ? sysfs_write_file+0xe5/0x170
[  276.616142]  [<ffffffff811887b8>] ? vfs_write+0xb8/0x1a0
[  276.632607]  [<ffffffff811890b1>] ? sys_write+0x51/0x90
[  276.648671]  [<ffffffff8100c072>] ? system_call_fastpath+0x16/0x1b
[  276.664756] ---[ end trace 9f5d4fcdd0c3edfc ]---

We forget to clear BCACHE_DEV_UNLINK_DONE flag in bcache_device_attach()
function when we attach a backing device first time.  After detaching this
backing device, this flag will be true and sysfs_remove_link() isn't called in
bcache_device_unlink().  Then when we attach this backing device again,
sysfs_create_link() will return EEXIST error in bcache_device_link().

So the fix is trival and we clear this flag in bcache_device_link().

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Tested-by: Joshua Schmid <jschmid@suse.com>
Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-30 20:23:08 -07:00
Kent Overstreet
c5f1e5adf9 bcache: Add a cond_resched() call to gc
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-30 20:23:06 -07:00
Zheng Liu
2ef9ccbfcb bcache: fix a livelock when we cause a huge number of cache misses
Subject :	[PATCH v2] bcache: fix a livelock in btree lock
Date :	Wed, 25 Feb 2015 20:32:09 +0800 (02/25/2015 04:32:09 AM)

This commit tries to fix a livelock in bcache.  This livelock might
happen when we causes a huge number of cache misses simultaneously.

When we get a cache miss, bcache will execute the following path.

->cached_dev_make_request()
  ->cached_dev_read()
    ->cached_lookup()
      ->bch->btree_map_keys()
        ->btree_root()  <------------------------
          ->bch_btree_map_keys_recurse()        |
            ->cache_lookup_fn()                 |
              ->cached_dev_cache_miss()         |
                ->bch_btree_insert_check_key() -|
                  [If btree->seq is not equal to seq + 1, we should return
                   EINTR and traverse btree again.]

In bch_btree_insert_check_key() function we first need to check upgrade
flag (op->lock == -1), and when this flag is true we need to release
read btree->lock and try to take write btree->lock.  During taking and
releasing this write lock, btree->seq will be monotone increased in
order to prevent other threads modify this in cache miss (see btree.h:74).
But if there are some cache misses caused by some requested, we could
meet a livelock because btree->seq is always changed by others.  Thus no
one can make progress.

This commit will try to take write btree->lock if it encounters a race
when we traverse btree.  Although it sacrifice the scalability but we
can ensure that only one can modify the btree.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Tested-by: Joshua Schmid <jschmid@suse.com>
Tested-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: Joshua Schmid <jschmid@suse.com>
Cc: Zhu Yanhai <zhu.yanhai@gmail.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-30 20:23:05 -07:00
NeilBrown
312045eef9 md: remove check for MD_RECOVERY_NEEDED in action_store.
md currently doesn't allow a 'sync_action' such as 'reshape' to be set
while MD_RECOVERY_NEEDED is set.

This s a problem, particularly since commit 738a273806ee as that can
cause ->check_shape to call mddev_resume() which sets
MD_RECOVERY_NEEDED.  So by the time we come to start 'reshape' it is
very likely that MD_RECOVERY_NEEDED is still set.

Testing for this flag is not really needed and is in any case very
racy as it can be set at any moment - asynchronously.  Any race
between setting a sync_action and setting MD_RECOVERY_NEEDED must
already be handled properly in some locked code, probably
md_check_recovery(), so remove the test here.

The test on MD_RECOVERY_RUNNING is also racy in the 'reshape' case
so we should test it again after getting mddev_lock().

As this fixes a race and a regression which can cause 'reshape' to
fail, it is suitable for -stable kernels since 4.1

Reported-by: Xiao Ni <xni@redhat.com>
Fixes: 738a273806ee ("md/raid5: fix allocation of 'scribble' array.")
Cc: stable@vger.kernel.org (v4.1+)
Signed-off-by: NeilBrown <neilb@suse.com>
2015-12-21 11:10:06 +11:00
Goldwyn Rodrigues
cb01c5496d Fix remove_and_add_spares removes drive added as spare in slot_store
Commit 2910ff17d154baa5eb50e362a91104e831eb2bb6
introduced a regression which would remove a recently added spare via
slot_store. Revert part of the patch which touches slot_store() and add
the disk directly using pers->hot_add_disk()

Fixes: 2910ff17d154 ("md: remove_and_add_spares() to activate specific
rdev")
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Pawel Baldysiak <pawel.baldysiak@intel.com>
Signed-off-by: NeilBrown <neilb@suse.com>
2015-12-18 15:19:16 +11:00
Mikulas Patocka
0dc10e50f2 md: fix bug due to nested suspend
The patch c7bfced9a6716ff66c9d61f934bb60af08d4688c committed to 4.4-rc
causes crash in LVM test shell/lvchange-raid.sh. The kernel crashes with
this BUG, the reason is that we attempt to suspend a device that is
already suspended. See also
https://bugzilla.redhat.com/show_bug.cgi?id=1283491

This patch fixes the bug by changing functions mddev_suspend and
mddev_resume to always nest.
The number of nested calls to mddev_nested_suspend is kept in the
variable mddev->suspended.
[neilb: made mddev_suspend() always nest instead of introduce mddev_nested_suspend]

kernel BUG at drivers/md/md.c:317!
CPU: 3 PID: 32754 Comm: lvm Not tainted 4.4.0-rc2 #1
task: 0000000047076040 ti: 0000000047014000 task.ti: 0000000047014000

     YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI
PSW: 00001000000001000000000000001111 Not tainted
r00-03  000000000804000f 00000000102c5280 0000000010c7522c 000000007e3d1810
r04-07  0000000010c6f000 000000004ef37f20 000000007e3d1dd0 000000007e3d1810
r08-11  000000007c9f1600 0000000000000000 0000000000000001 ffffffffffffffff
r12-15  0000000010c1d000 0000000000000041 00000000f98d63c8 00000000f98e49e4
r16-19  00000000f98e49e4 00000000c138fd06 00000000f98d63c8 0000000000000001
r20-23  0000000000000002 000000004ef37f00 00000000000000b0 00000000000001d1
r24-27  00000000424783a0 000000007e3d1dd0 000000007e3d1810 00000000102b2000
r28-31  0000000000000001 0000000047014840 0000000047014930 0000000000000001
sr00-03  0000000007040800 0000000000000000 0000000000000000 0000000007040800
sr04-07  0000000000000000 0000000000000000 0000000000000000 0000000000000000

IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000102c538c 00000000102c5390
 IIR: 03ffe01f    ISR: 0000000000000000  IOR: 00000000102b2748
 CPU:        3   CR30: 0000000047014000 CR31: 0000000000000000
 ORIG_R28: 00000000000000b0
 IAOQ[0]: mddev_suspend+0x10c/0x160 [md_mod]
 IAOQ[1]: mddev_suspend+0x110/0x160 [md_mod]
 RP(r2): raid1_add_disk+0xd4/0x2c0 [raid1]
Backtrace:
 [<0000000010c7522c>] raid1_add_disk+0xd4/0x2c0 [raid1]
 [<0000000010c20078>] raid_resume+0x390/0x418 [dm_raid]
 [<00000000105833e8>] dm_table_resume_targets+0xc0/0x188 [dm_mod]
 [<000000001057f784>] dm_resume+0x144/0x1e0 [dm_mod]
 [<0000000010587dd4>] dev_suspend+0x1e4/0x568 [dm_mod]
 [<0000000010589278>] ctl_ioctl+0x1e8/0x428 [dm_mod]
 [<0000000010589518>] dm_compat_ctl_ioctl+0x18/0x68 [dm_mod]
 [<0000000040377b88>] compat_SyS_ioctl+0xd0/0x1558

Fixes: c7bfced9a671 ("md: suspend i/o during runtime blk_integrity_unregister")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
2015-12-18 15:19:16 +11:00
Shaohua Li
9b15603dbd MD: change journal disk role to disk 0
Neil pointed out setting journal disk role to raid_disks will confuse
reshape if we support reshape eventually. Switching the role to 0 (we
should be fine as long as the value >=0) and skip sysfs file creation to
avoid error.

Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
2015-12-18 15:19:16 +11:00
Artur Paszkiewicz
cc57858831 md/raid10: fix data corruption and crash during resync
The commit c31df25f20e3 ("md/raid10: make sync_request_write() call
bio_copy_data()") replaced manual data copying with bio_copy_data() but
it doesn't work as intended. The source bio (fbio) is already processed,
so its bvec_iter has bi_size == 0 and bi_idx == bi_vcnt.  Because of
this, bio_copy_data() either does not copy anything, or worse, copies
data from the ->bi_next bio if it is set.  This causes wrong data to be
written to drives during resync and sometimes lockups/crashes in
bio_copy_data():

[  517.338478] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [md126_raid10:3319]
[  517.347324] Modules linked in: raid10 xt_CHECKSUM ipt_MASQUERADE nf_nat_masquerade_ipv4 tun ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw iptable_filter ip_tables x86_pkg_temp_thermal coretemp kvm_intel kvm crct10dif_pclmul crc32_pclmul cryptd shpchp pcspkr ipmi_si ipmi_msghandler tpm_crb acpi_power_meter acpi_cpufreq ext4 mbcache jbd2 sr_mod cdrom sd_mod e1000e ax88179_178a usbnet mii ahci ata_generic crc32c_intel libahci ptp pata_acpi libata pps_core wmi sunrpc dm_mirror dm_region_hash dm_log dm_mod
[  517.440555] CPU: 0 PID: 3319 Comm: md126_raid10 Not tainted 4.3.0-rc6+ #1
[  517.448384] Hardware name: Intel Corporation PURLEY/PURLEY, BIOS PLYDCRB1.86B.0055.D14.1509221924 09/22/2015
[  517.459768] task: ffff880153773980 ti: ffff880150df8000 task.ti: ffff880150df8000
[  517.468529] RIP: 0010:[<ffffffff812e1888>]  [<ffffffff812e1888>] bio_copy_data+0xc8/0x3c0
[  517.478164] RSP: 0018:ffff880150dfbc98  EFLAGS: 00000246
[  517.484341] RAX: ffff880169356688 RBX: 0000000000001000 RCX: 0000000000000000
[  517.492558] RDX: 0000000000000000 RSI: ffffea0001ac2980 RDI: ffffea0000d835c0
[  517.500773] RBP: ffff880150dfbd08 R08: 0000000000000001 R09: ffff880153773980
[  517.508987] R10: ffff880169356600 R11: 0000000000001000 R12: 0000000000010000
[  517.517199] R13: 000000000000e000 R14: 0000000000000000 R15: 0000000000001000
[  517.525412] FS:  0000000000000000(0000) GS:ffff880174a00000(0000) knlGS:0000000000000000
[  517.534844] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  517.541507] CR2: 00007f8a044d5fed CR3: 0000000169504000 CR4: 00000000001406f0
[  517.549722] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  517.557929] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  517.566144] Stack:
[  517.568626]  ffff880174a16bc0 ffff880153773980 ffff880169356600 0000000000000000
[  517.577659]  0000000000000001 0000000000000001 ffff880153773980 ffff88016a61a800
[  517.586715]  ffff880150dfbcf8 0000000000000001 ffff88016dd209e0 0000000000001000
[  517.595773] Call Trace:
[  517.598747]  [<ffffffffa043ef95>] raid10d+0xfc5/0x1690 [raid10]
[  517.605610]  [<ffffffff816697ae>] ? __schedule+0x29e/0x8e2
[  517.611987]  [<ffffffff814ff206>] md_thread+0x106/0x140
[  517.618072]  [<ffffffff810c1d80>] ? wait_woken+0x80/0x80
[  517.624252]  [<ffffffff814ff100>] ? super_1_load+0x520/0x520
[  517.630817]  [<ffffffff8109ef89>] kthread+0xc9/0xe0
[  517.636506]  [<ffffffff8109eec0>] ? flush_kthread_worker+0x70/0x70
[  517.643653]  [<ffffffff8166d99f>] ret_from_fork+0x3f/0x70
[  517.649929]  [<ffffffff8109eec0>] ? flush_kthread_worker+0x70/0x70

Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Reviewed-by: Shaohua Li <shli@kernel.org>
Cc: stable@vger.kernel.org (v4.2+)
Fixes: c31df25f20e3 ("md/raid10: make sync_request_write() call bio_copy_data()")
Signed-off-by: NeilBrown <neilb@suse.com>
2015-12-18 15:19:16 +11:00
Nikolay Borisov
18d03e8c25 dm thin: fix race condition when destroying thin pool workqueue
When a thin pool is being destroyed delayed work items are
cancelled using cancel_delayed_work(), which doesn't guarantee that on
return the delayed item isn't running.  This can cause the work item to
requeue itself on an already destroyed workqueue.  Fix this by using
cancel_delayed_work_sync() which guarantees that on return the work item
is not running anymore.

Fixes: 905e51b39a555 ("dm thin: commit outstanding data every second")
Fixes: 85ad643b7e7e5 ("dm thin: add timeout to stop out-of-data-space mode holding IO forever")
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2015-12-17 15:47:20 -05:00
Mike Snitzer
512167788a dm space map metadata: remove unused variable in brb_pop()
Remove the unused struct block_op pointer that was inadvertantly
introduced, via cut-and-paste of previous brb_op() code, as part of
commit 50dd842ad.

(Cc'ing stable@ because commit 50dd842ad did)

Fixes: 50dd842ad ("dm space map metadata: fix ref counting bug when bootstrapping a new space map")
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2015-12-14 09:26:01 -05:00
Sami Tolvanen
0cc37c2df4 dm verity: add ignore_zero_blocks feature
If ignore_zero_blocks is enabled dm-verity will return zeroes for blocks
matching a zero hash without validating the content.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:39:03 -05:00
Sami Tolvanen
a739ff3f54 dm verity: add support for forward error correction
Add support for correcting corrupted blocks using Reed-Solomon.

This code uses RS(255, N) interleaved across data and hash
blocks. Each error-correcting block covers N bytes evenly
distributed across the combined total data, so that each byte is a
maximum distance away from the others. This makes it possible to
recover from several consecutive corrupted blocks with relatively
small space overhead.

In addition, using verity hashes to locate erasures nearly doubles
the effectiveness of error correction. Being able to detect
corrupted blocks also improves performance, because only corrupted
blocks need to corrected.

For a 2 GiB partition, RS(255, 253) (two parity bytes for each
253-byte block) can correct up to 16 MiB of consecutive corrupted
blocks if erasures can be located, and 8 MiB if they cannot, with
16 MiB space overhead.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:39:03 -05:00
Sami Tolvanen
bb4d73ac5e dm verity: factor out verity_for_bv_block()
verity_for_bv_block() will be re-used by optional dm-verity object.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:39:02 -05:00
Sami Tolvanen
ffa393807c dm verity: factor out structures and functions useful to separate object
Prepare for an optional verity object to make use of existing dm-verity
structures and functions.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:39:01 -05:00
Sami Tolvanen
03045cbafa dm verity: move dm-verity.c to dm-verity-target.c
Prepare for extending dm-verity with an optional object.  Follows the
naming convention used by other DM targets (e.g. dm-cache and dm-era).

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:39:01 -05:00
Sami Tolvanen
753c1fd028 dm verity: separate function for parsing opt args
Move optional argument parsing into a separate function to make it
easier to add more of them without making verity_ctr even longer.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:39:00 -05:00
Sami Tolvanen
6dbeda3469 dm verity: clean up duplicate hashing code
Handle dm-verity salting in one place to simplify the code.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:39:00 -05:00
Mike Snitzer
ba503835ad dm btree: factor out need_insert() helper
Eliminates code duplication within insert().

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:38:59 -05:00
Anup Limbu
86a49e2dac dm bufio: use BUG_ON instead of conditional call to BUG
Signed-off-by: Anup Limbu <anuplimbu14@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:38:58 -05:00
Mikulas Patocka
86bad0c707 dm bufio: store stacktrace in buffers to help find buffer leaks
The option DM_DEBUG_BLOCK_STACK_TRACING is moved from persistent-data
directory to device mapper directory because it will now be used by
persistent-data and bufio.  When the option is enabled, each bufio buffer
stores the stacktrace of the last dm_bufio_get(), dm_bufio_read() or
dm_bufio_new() call that increased the hold count to 1.  The buffer's
stacktrace is printed if the buffer was not released before the bufio
client is destroyed.

When DM_DEBUG_BLOCK_STACK_TRACING is enabled, any bufio buffer leaks are
considered warnings - i.e. the kernel continues afterwards.  If not
enabled, buffer leaks are considered BUGs and the kernel with crash.
Reasoning on this disposition is: if we only ever warned on buffer leaks
users would generally ignore them and the problematic code would never
get fixed.

Successfully used to find source of bufio leaks fixed with commit
fce079f63c3 ("dm btree: fix bufio buffer leaks in dm_btree_del() error
path").

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:38:58 -05:00
Mikulas Patocka
f98c8f7970 dm bufio: return NULL to improve code clarity
A small code cleanup in new_read() - return NULL instead of b (although
b is NULL at this point).  This function is not returning pointer to the
buffer, it is returning a pointer to the bufffer's data, thus it makes
no sense to return the variable b.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:38:57 -05:00
Mikulas Patocka
313c9b9736 dm block manager: cleanup code that prints stacktrace
There is no need to record stack trace and immediately print it.  Just
use dump_stack() to print the current stack.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:38:56 -05:00
Mikulas Patocka
fe3265b180 dm: don't save and restore bi_private
Device mapper used the field bi_private to point to dm_target_io. However,
since kernel 3.15, the bi_private field is unused, and so the targets do
not need to save and restore this field.

This patch removes code that saves and restores bi_private from dm-cache,
dm-snapshot and dm-verity.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:38:56 -05:00
Joe Thornber
086fbbbda9 dm thin metadata: make dm_thin_find_mapped_range() atomic
Refactor dm_thin_find_mapped_range() so that it takes the read lock on
the metadata's lock; rather than relying on finer grained locking that
is pushed down inside dm_thin_find_next_mapped_block() and
dm_thin_find_block().

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:38:55 -05:00
Joe Thornber
3d5f67332a dm thin metadata: speed up discard of partially mapped volumes
Use dm_btree_lookup_next() to more quickly discard partially mapped
volumes.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-12-10 10:30:56 -05:00
Joe Thornber
ed8b45a367 dm btree: fix bufio buffer leaks in dm_btree_del() error path
If dm_btree_del()'s call to push_frame() fails, e.g. due to
btree_node_validator finding invalid metadata, the dm_btree_del() error
path must unlock all frames (which have active dm-bufio buffers) that
were pushed onto the del_stack.

Otherwise, dm_bufio_client_destroy() will BUG_ON() because dm-bufio
buffers have leaked, e.g.:
  device-mapper: bufio: leaked buffer 3, hold count 1, list 0

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2015-12-10 10:30:18 -05:00
Joe Thornber
50dd842ad8 dm space map metadata: fix ref counting bug when bootstrapping a new space map
When applying block operations (BOPs) do not remove them from the
uncommitted BOP ring-buffer until after they've been applied -- in case
we recurse.

Also, perform BOP_INC operation, in dm_sm_metadata_create() and
sm_metadata_extend(), in terms of the uncommitted BOP ring-buffer rather
than using direct calls to sm_ll_inc().

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2015-12-09 13:27:25 -05:00
Joe Thornber
49e99fc717 dm thin metadata: fix bug when taking a metadata snapshot
When you take a metadata snapshot the btree roots for the mapping and
details tree need to have their reference counts incremented so they
persist for the lifetime of the metadata snap.

The roots being incremented were those currently written in the
superblock, which could possibly be out of date if concurrent IO is
triggering new mappings, breaking of sharing, etc.

Fix this by performing a commit with the metadata lock held while taking
a metadata snapshot.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2015-12-09 13:18:12 -05:00
Masanari Iida
e3d132d123 treewide: Fix typos in printk
This patch fix multiple spelling typos found in
various part of kernel.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2015-12-08 14:59:19 +01:00
Joe Thornber
993ceab919 dm thin metadata: fix bug in dm_thin_remove_range()
dm_btree_remove_leaves() only unmaps a contiguous region so we need a
loop, in __remove_range(), to handle ranges that contain multiple
regions.

A new btree function, dm_btree_lookup_next(), is introduced which is
more efficiently able to skip over regions of the thin device which
aren't mapped.  __remove_range() uses dm_btree_lookup_next() for each
iteration of __remove_range()'s loop.

Also, improve description of dm_btree_remove_leaves().

Fixes: 6550f075 ("dm thin metadata: add dm_thin_remove_range()")
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # 4.1+
2015-12-02 13:26:49 -05:00
Mike Snitzer
30ce6e1cc5 dm btree: fix leak of bufio-backed block in btree_split_sibling error path
The block allocated at the start of btree_split_sibling() is never
released if later insert_at() fails.

Fix this by releasing the previously allocated bufio block using
unlock_block().

Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2015-12-02 13:20:34 -05:00
Mike Snitzer
0fcb04d593 dm thin: fix regression in advertised discard limits
When establishing a thin device's discard limits we cannot rely on the
underlying thin-pool device's discard capabilities (which are inherited
from the thin-pool's underlying data device) given that DM thin devices
must provide discard support even when the thin-pool's underlying data
device doesn't support discards.

Users were exposed to this thin device discard limits regression if
their thin-pool's underlying data device does _not_ support discards.
This regression caused all upper-layers that called the
blkdev_issue_discard() interface to not be able to issue discards to
thin devices (because discard_granularity was 0).  This regression
wasn't caught earlier because the device-mapper-test-suite's extensive
'thin-provisioning' discard tests are only ever performed against
thin-pool's with data devices that support discards.

Fix is to have thin_io_hints() test the pool's 'discard_enabled' feature
rather than inferring whether or not a thin device's discard support
should be enabled by looking at the thin-pool's discard_granularity.

Fixes: 216076705 ("dm thin: disable discard support for thin devices if pool's is disabled")
Reported-by: Mike Gerber <mike@sprachgewalt.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # 4.1+
2015-11-23 14:54:46 -05:00
Mikulas Patocka
bcbd94ff48 dm crypt: fix a possible hang due to race condition on exit
A kernel thread executes __set_current_state(TASK_INTERRUPTIBLE),
__add_wait_queue, spin_unlock_irq and then tests kthread_should_stop().
It is possible that the processor reorders memory accesses so that
kthread_should_stop() is executed before __set_current_state().  If such
reordering happens, there is a possible race on thread termination:

CPU 0:
calls kthread_should_stop()
	it tests KTHREAD_SHOULD_STOP bit, returns false
CPU 1:
calls kthread_stop(cc->write_thread)
	sets the KTHREAD_SHOULD_STOP bit
	calls wake_up_process on the kernel thread, that sets the thread
	state to TASK_RUNNING
CPU 0:
sets __set_current_state(TASK_INTERRUPTIBLE)
spin_unlock_irq(&cc->write_thread_wait.lock)
schedule() - and the process is stuck and never terminates, because the
	state is TASK_INTERRUPTIBLE and wake_up_process on CPU 1 already
	terminated

Fix this race condition by using a new flag DM_CRYPT_EXIT_THREAD to
signal that the kernel thread should exit.  The flag is set and tested
while holding cc->write_thread_wait.lock, so there is no possibility of
racy access to the flag.

Also, remove the unnecessary set_task_state(current, TASK_RUNNING)
following the schedule() call.  When the process was woken up, its state
was already set to TASK_RUNNING.  Other kernel code also doesn't set the
state to TASK_RUNNING following schedule() (for example,
do_wait_for_common in completion.c doesn't do it).

Fixes: dc2676210c42 ("dm crypt: offload writes to thread")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-11-19 13:38:30 -05:00
Junichi Nomura
43e43c9ea6 dm mpath: fix infinite recursion in ioctl when no paths and !queue_if_no_path
In multipath_prepare_ioctl(),
  - pgpath is a path selected from available paths
  - m->queue_io is true if we cannot send a request immediately to
    paths, either because:
      * there is no available path
      * the path group needs activation (pg_init)
          - pg_init is not started
          - pg_init is still running
  - m->queue_if_no_path is true if the device is configured to queue
    I/O if there are no available paths

If !pgpath && !m->queue_if_no_path, the handler should return -EIO.
However in the course of refactoring the condition check has broken
and returns success in that case.  Since bdev points to the dm device
itself, dm_blk_ioctl() calls __blk_dev_driver_ioctl() for itself and
recurses until crash.

You could reproduce the problem like this:

  # dmsetup create mp --table '0 1024 multipath 0 0 0 0'
  # sg_inq /dev/mapper/mp
  <crash>
  [  172.648615] BUG: unable to handle kernel paging request at fffffffc81b10268
  [  172.662843] PGD 19dd067 PUD 0
  [  172.666269] Thread overran stack, or stack corrupted
  [  172.671808] Oops: 0000 [#1] SMP
  ...

Fix the condition check with some clarifications.

Fixes: e56f81e0b01e ("dm: refactor ioctl handling")
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-11-17 14:19:00 -05:00
Mike Snitzer
647a20d5ca dm: do not reuse dm_blk_ioctl block_device input as local variable
(Ab)using the @bdev passed to dm_blk_ioctl() opens the potential for
targets' .prepare_ioctl to fail if they go on to check the bdev for
!NULL.

Fixes: e56f81e0b01e ("dm: refactor ioctl handling")
Reported-by: Junichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-11-17 14:18:49 -05:00
Junichi Nomura
5bbbfdf685 dm: fix ioctl retry termination with signal
dm-mpath retries ioctl, when no path is readily available and the device
is configured to queue I/O in such a case. If you want to stop the retry
before multipathd decides to turn off queueing mode, you could send
signal for the process to exit from the loop.

However the check of fatal signal has not carried along when commit
6c182cd88d17 ("dm mpath: fix ioctl deadlock when no paths") moved the
loop from dm-mpath to dm core. As a result, we can't terminate such
a process in the retry loop.

Easy reproducer of the situation is:

  # dmsetup create mp --table '0 1024 multipath 0 0 0 0'
  # dmsetup message mp 0 'queue_if_no_path'
  # sg_inq /dev/mapper/mp

then you should be able to terminate sg_inq by pressing Ctrl+C.

Fixes: 6c182cd88d17 ("dm mpath: fix ioctl deadlock when no paths")
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2015-11-17 14:04:32 -05:00